Thermostatic engine starter



A ril 11, 1967 D. BISSON THERMQSTATIG ENGINE STARTER 2 Sheets-Shet 1 Filed Oct. 23, 1964 Den/s B1550 ,4 TTURIVEYS April 11, 1967 D. BISSON THERMOSTATIC ENGINE STARTER 2 Sheets-Sheet Filed Oct. 23, 1964 llllllllvulllllL CA BURETOYR luIIl-Illlllll //V VfN TOR Denis 8/55. 0 BY ATTORNEYS United States Patent 3,313,947 THEOSTATEC ENGINE STARTER Denis Bisson, Argenteuil C0., Lachute, Quebec, Canada Filed Oct. 23, 1964, Ser. No. 406,110 6 Claims. (Cl. 29038) The instant invention relatesto a thermostatic engine starter and more particularly to a device for connection in the ignition system, heater and starter motor circuit of a motor vehicle to cause starting of the motor and heater whenever the temperature of the air reaches a predetermined low degree and to cause cutting off of the heater and motor after the latter has warmed up suificiently.

The main object of the invention resides in the provision of such a device that can be manufactured at an extremely low cost as it can easily be made of a very small number of simple parts. The device is however quite efiicient in operation and can be adjusted to operate at different temperatures.

Another object of the invention resides in providing a thermostatic engine starter that can be mounted in a very small casing and sold as a unit with all the necessary electrical wiring outlets for ready connection to the electrical wiring system of an automobile.

The above noted objects may be obtained in a thermostatic engine starter made according to the invention which comprises: a first and a second electricallynon-conductive U-tube, each tube formed of a pair of bottom-interconnected legs; a bath of mercury in each of said tubes defining in each leg a column of mercury having a free level; means defining a closed thermostatic gas chamber in one leg of the first tube above the corresponding mercury level; a connection electrically joining the mercury baths in said tubes; a first electrode through said first tube projecting in the thermostatic gas chamber above the. mercury level, in non-operative condition of the starter; a second electrode through one of the legs of the second tube and above the mercury level in the said one leg, in non-operative condition of the starter; a third electrode through the other leg of the second tube and within the mercury column in the said other leg, in non-operative condition of the starter.

The overall combination capable of warming up a car in cold weather, further comprises a power source, an ignition circuit having an ignition coil, a starter motor and a heater. Means is provided for connecting one terminal of the coil, starter motor and heater toone electrical terminal of the power source; further means connect the other electrical terminal of the coil to the connection between the mercury baths in the tubes; another means connect the first electrode to the other terminal of the power source; a still further electrical means connect the second electrode to the other electrical terminal of the starter motor while a further means connect the third electrode to the other electrical terminal of the heater.

A better understanding of the invention will be atforded by the description that follows having reference to the appended drawing, wherein:

FIG. 1 is a perspective view of a cabinet or casing containing the engine starter of the invention;

FIG. 2 is a perspective view of the cabinet or casing of FIG. 1 with one half-part removed;

FIG. 3 is an electrical connection between one of the tubes and the casing, shown on an enlarged scale and in vertical cross-section;

FIGS. 4 and 5 are vertical cross-sectional views of the engine starter of the invention as shown coupled to the electrical circuit in both inoperative and operative conditions of the starter.

The invention will be seen, particular reference being made to FIG. 2, to consist of a pair of U-tubes 1, 3 con- 3,313,947 Patented Apr. 11, 1967 nected by means of a connection 5. Tube 1 has, at one end thereof, a thermostatic air chamber 7 while the other end is open to atmosphere. Tube 3 is also open, at one end, to atmosphere while the other end is closed.

Both tubes are mounted in a casing 9 formed of two mating half parts 11 joined together by any known means such'as screws 13 driven at each corner thereof. Tubes 1 and 3 are made of electrically non-conductive material while casing 9 may be made of conductive or non-conductive material, as will now be explained.

Tubes '1 and 3 are fixed in one of the casing half parts 11 by three supports 15 positioned at predetermined locations as will be explained later. All connections may be alike and a preferred form is shown in FIG. 3, wherein it will be seen that an electrically conductive threaded member 17 is secured to the non-conductive tube in such a manner as to project completely through the wall thereof and into the inside of the tube to form an electrode 19. Threaded member 17 also projects through the wall of the half part 11 and is secured thereto in any known manner such as by a pair of nuts 21 tightened against the Wall of half part 11. If the said casing 9 is made of electri cally-conductive material, then an insulating sleeve 22 must be used to ensure that there is no electrical contact between threaded member 17, nuts 21 and casing 9.

An electrical connection may be taken from the threaded member 17 in any known manner such as by the use of a ring connector 23 to which is secured a lead wire 25.

Now that the general assembly has been described, further features of the invention and its connection to the electrical circuitry of a motor will be explained with particular relation to FIGS. 4 and 5.

As shown, each tube 1, 3 is formed of a pair of bottom interconnected legs 2 and 4, for tube 1, and 6 and 8, for tube 3.

A bath of mercury 27, 27' is provided in each of tubes 1 and 3 which, of course, spread evenly in each of the tubes, in non-operative condition of the starter.

Means is provided to define a closed thermostatic gas chamber 29 in leg 2 of tube 1 above the mercury level. The said means comprises a metered chamber formed of a hollow housing 31 defined by a cylinder 33 in which a piston 35 is slidably displaceable by means of a threaded rod 37 threading through a wall of cylinder 33 and operthat the means defining a thermostatic chamber comprises.

a housing 31 having a manually movable end wall 35 whereby the inner volume thereof may be varied.

Leg 4 of tube 1 is opened to atmosphere while leg 6 is connected to the carburator 43 of the engine and leg 8 is closed.

A first electrode '19 is provided through leg 2, in gas chamber 29, and slightly above the level of the column of mercury 27. A second electrode 19' is provided through the wall of leg 6 also slightly above the bath of mercury 27 in tube 3. Finally, a third electrode 19 is provided through the wall of leg 8 but this time to open in the bath of mercury 27 in tube 3. Each electrode 19, 19, 19-" is of the type illustrated in FIG. 3 and above-described.

The electrical circuitry, of interest in this description, comprises the power source or battery B, the starter motor S, the heater H and the ignition circuit identified here only by the ignition coil C. Starting motor S, heater H and coil C all have one electrical terminal connected to one electrical terminal of battery B. An electrical line 45 connects the first electrode 19 to the second terminal of the power source B. A manually operable switch 46 is provided in said line 45.

A second electrical line connects connection 5 between the two mercury baths 2'7, 27 to the second terminal of the ignition coil C, a third electrical line 49' joins the second electrode 19 to the second terminal of heater H while a fourth electrical line connects the third electrode 19" to the starter motor S.

With the above description in mind, the operation of the device is as follows:

First, the car owner closes the manual switch 46 for the night. At that time, the car is warm and gas (preferably air) in chamber 29 is fully expanded so that the mercury in leg 2 of tube 1 does not reach electrode 19. However, as the temperature drops and the gas in chamber 29 cools, the column of mercury in leg 2. rises and finally contacts electrode 19. It will be understood, here, that the temperature at which this first contact is made may be regulated by adjusting the volume in housing 31 by displacing the movable wall 35 through rotation of operating knob 39.

Current then flows from battery B, through line 45 and electrode 19 through bath 27, line 47 to energize coi-l C, and through bath 27 to simultaneously start the starter motor S.

As soon as the starter motor starts, the leg 6 of tube 3 is placed under vacuum since it is connected to the carburator 43' and mercury 27' rises to touch second electrode 19' to thus start off heater H since current then flows through line 49. Almost immediately also, the mercury 27 falls in leg *8 of tube 3 to break off contact with third electrode 19 and cut off the starter motor from the power source B. It will be noted that coil C remains energized. The total condition is that illustrated in FIG. 5.

As the motor warms up, air in chamber 29 expands since the apparatus is intended to be located close to the motor body so as to be warmed thereby.

After a while, the column of mercury H in leg 2 will be pushed past first electrode 19 and the complete electrical circuit cut off. Coil C will be deenergized and the engine motor will stop. At the same time, the vacuum in leg 6 of tube 3 will break'and the mercury 27' in tube 3 will resume the position shown in FIG. 4. Of course, as soon as electrode 19 is out of contact with mercury 27 no electricity flows to the heater which is instantaneously cut off.

Leg 8 is closed at the top, as said previously to prevent emptying of tube 3 of mercury under the eifect of the vacuum created by carburator 43.

The position of connection in relation to the mercury level in leg 4 should be such that should the motor fail to start even after the mercury in leg 2 has reached electrode 19, further rising of the mercury will soon allow connection 5 to emerge from the mercury in leg 4 thus deenergizing both coil'C and starter motor S to prevent complete discharge of the battery.

Another beneficial action in the engine starter of the invention lies in that if the engine fails to start, the delayed recovery of atmospheric pressure in leg 6 results in a waiting period before the starter motor S is energized again, that is, before mercury in leg 8 reaches electrode 19" again.

The conventional ignition switch 50 and its connections to the starter motor S, the heater H, and the ignition coil C have been shown in dotted lines as they do not form part of the invention. It will however be noted that the various connections to the engine starter of the invention by-pass switch 50. Operation of the engine starter, as explained above, is independent of the ignition switch 50 and only depend on the temperature of the air in chamber 29.

Although a specific embodiment of the invention has just been described, it will be understood that various modifications may be made thereto without departing from the spirit thereof as set forth in the appended claims.

I claim:

1. A thermostatic switching device for automatically starting and stopping an internal combustion engine havstanding U-tube, each tube formed of a pair of bottom-interconnected legs;

(b) a bath of mercury in each of said tubes defining in each leg a column of mercury having a free level;

(c) means defining a closed thermostatic gas chamber in one leg of said first tube above the corresponding mercury level;

(d) a connection electrically joining the mercury baths e in said tubes; the said connection adapted to be connected to the other terminal of said coil;

(e) a first electrode through said first tube projecting, in non-operative condition of said starter, in said chamber above the mercury level, the said first electrode adapted to be connected to the other terminal of said coil;

(f) a second electrode through one of the legs of said second tube and, in non-operative condition of said starter, above the mercury level in said one leg; the said second electrode adapted to be connected to the other terminal of the starter motor;

(g) a third electrode through the other leg of said second tube and, in non-operative condition of the starter, within the mercury column in the said other leg, said other leg being closed at the top thereof, the said third electrode adapted to be connected to the other terminal of the heater.

2. A starter as claimed in claim 1, wherein said means defining said thermostatic gas chamber comprises:

a hollow casing having a manually movable end wal whereby the inner volume of said casing may be varied, and 7 means placing said inner volume in communication with said one leg of said first tube. 3. A starter as claimed in claim 1, wherein said first electrode is so located in relation to said mercury level i in said first tube that, upon cooling of the gas in said thermostatic gas chamber to a predetermined temperature and subsequent contraction thereof, the mercury level reaches and contacts said first electrode.

4. A starter as claimed in claim 3, including means responsive to contact of said first electrode by the mercury in said first tube, creating a vacuum in said one of the legs of said second tube, to cause rising of the mercury therein to contact said second electrode; said third electrode being so located in relation to said level of the mercury column in said other leg that it emerges therefrom as the mercury column in said one of the legs of the second tube rises. 5. A thermostatic engine starter combination comprismg:

(a) a power source, an ignition circuit having an ignition coil, a starter motor and a heater;

(b) means connecting one electrical terminal of each of said coil, starter motor and heater to one electrical terminal of said power source;

(c) a first and second electrically non-conductive upstanding U tube, each tube formed of a pair of bottom-interconnected legs;

(d) a bath of mercury in each of said tubes defining in each leg a column of mercury having a free level;

(e) means defining a closed thermostatic gas chamber in one leg of said first tube above the corresponding mercury level;

(f) a connection electrically joining the mercury baths in said tube;

(g) means electrically connecting the other electrica terminal of said coil to said connection;

(h) a first electrode through said first tube projecting, in non-operative condition of said starter, in said chamber above the mercury level;

(i) means electrically connecting said first electrode to the other electrical terminal of said power source;

v 5 (j) a second electrode through one of the legs of said 6. A combination as claimed in claim 5, including an second tube and, in non-operative condition of said on-off switch on the'means connecting said first electrode starter, above the mercury level in said one leg; (k) means connecting said second electrode to the other electrical terminal of said starter motor; 5 (l) a third electrode through the other leg of said second tube and, in non-operative condition of said starter, within the mercury column in the said other ORIS RADER Pnmmy Exammer' leg, said other leg being closed at the top thereof; SIMMONS, Assistant Examinen (m) means connecting said third electrode to the other 10 electrical terminal of said heater.

to the other terminal of said power source.

No references cited. 

1. A THERMOSTATIC SWITCHING DEVICE FOR AUTOMATICALLY STARTING AND STOPPING AN INTERNAL COMBUSTION ENGINE HAVING AN IGNITION COIL, A STARTER MOTOR AND A HEATER WHICH HAVE A TERMINAL CONNECTED TO A POWER SOURCE, THE SAID DEVICE COMPRISING IN COMBINATION: (A) A FIRST AND SECOND ELECTRICALLY NON-CONDUCTIVE UPSTANDING U-TUBE, EACH TUBE FORMED OF A PAIR OF BOTTOM-INTERCONNECTED LEGS; (B) A BATH OF MERCURY IN EACH OF SAID TUBES DEFINING IN EACH LEG A COLUMN OF MERCURY HAVING A FREE LEVEL; (C) MEANS DEFINING A CLOSED THERMOSTATIC GAS CHAMBER IN ONE LEG OF SAID FIRST TUBE ABOVE THE CORRESPONDING MERCURY LEVEL; (D) A CONNECTION ELECTRICALLY JOINING THE MERCURY BATHS IN SAID TUBES; THE SAID CONNECTION ADAPTED TO BE CONNECTED TO THE OTHER TERMINAL OF SAID COIL; (E) A FIRST ELECTRODE THROUGH SAID FIRST TUBE PROJECTING, IN NON-OPERATIVE CONDITION OF SAID STARTER, IN SAID CHAMBER ABOVE THE MERCURY LEVEL, THE SAID FIRST ELECTRODE ADAPTED TO BE CONNECTED TO THE OTHER TERMINAL OF SAID COIL; (F) A SECOND ELECTRODE THROUGH ONE OF THE LEGS OF SAID SECOND TUBE AND, IN NON-OPERATIVE CONDITION OF SAID STARTER, ABOVE THE MERCURY LEVEL IN SAID ONE LEG; THE SAID SECOND ELECTRODE ADAPTED TO BE CONNECTED TO THE OTHER TERMINAL OF THE STARTER MOTOR; (G) A THIRD ELECTRODE THROUGH THE OTHER LEG OF SAID SECOND TUBE AND, IN NON-OPERATIVE CONDITION OF THE STARTER, WITHIN THE MERCURY COLUMN IN THE SAID OTHER LEG, SAID OTHER LEG BEING CLOSED AT THE TOP THEREOF, THE SAID THIRD ELECTRODE ADAPTED TO BE CONNECTED TO THE OTHER TERMINAL OF THE HEATER. 